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Message-ID: <1540591147.66186.127.camel@acm.org>
Subject: Re: [PATCH] libosd: Remove ignored __weak attribute
From:   Bart Van Assche <bvanassche@acm.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     ooo@electrozaur.com, Nathan Chancellor <natechancellor@gmail.com>,
        "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        linux-scsi@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
        hch@infradead.org
Date:   Fri, 26 Oct 2018 14:59:07 -0700
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On Fri, 2018-10-26 at 14:36 -0700, Nick Desaulniers wrote:
+AD4 On Fri, Oct 26, 2018 at 2:30 PM Bart Van Assche +ADw-bvanassche+AEA-acm.org+AD4 wrote:
+AD4 +AD4 
+AD4 +AD4 On Fri, 2018-10-26 at 14:00 -0700, Nick Desaulniers wrote:
+AD4 +AD4 +AD4 On Fri, Oct 26, 2018 at 11:01 AM Bart Van Assche +ADw-bvanassche+AEA-acm.org+AD4 wrote:
+AD4 +AD4 +AD4 +AD4 
+AD4 +AD4 +AD4 +AD4 On Fri, 2018-10-26 at 10:54 -0700, Nick Desaulniers wrote:
+AD4 +AD4 +AD4 +AD4 +AD4 If creating one instance of this variable is a functional change, I
+AD4 +AD4 +AD4 +AD4 +AD4 can't help but suspect the original code was wrong.  But maybe Bart,
+AD4 +AD4 +AD4 +AD4 +AD4 Boaz, or Christoph can clarify or have more thoughts on this?  Looks
+AD4 +AD4 +AD4 +AD4 +AD4 like Boaz added this header in commit de258bf5e638 (+ACIAWw-SCSI+AF0 libosd:
+AD4 +AD4 +AD4 +AD4 +AD4 OSDv1 Headers+ACI).
+AD4 +AD4 +AD4 +AD4 
+AD4 +AD4 +AD4 +AD4 Hi Nick and Nathan,
+AD4 +AD4 +AD4 +AD4 
+AD4 +AD4 +AD4 +AD4 Had you noticed the following e-mail from early October:
+AD4 +AD4 +AD4 +AD4 https://marc.info/?l+AD0-linux-kernel+ACY-m+AD0-153849955503249?
+AD4 +AD4 +AD4 
+AD4 +AD4 +AD4 From this subthread with Linus, removal of the exofs fs and scsi osd
+AD4 +AD4 +AD4 code would be a user visible change and is not an option. See:
+AD4 +AD4 +AD4 https://lkml.org/lkml/2018/10/27/3
+AD4 +AD4 +AD4 https://lkml.org/lkml/2018/10/27/44
+AD4 +AD4 
+AD4 +AD4 Hi Nick,
+AD4 +AD4 
+AD4 +AD4 Linus wrote that removing a filesystem is considered a userspace breakage
+AD4 +AD4 if a user notices. The key part is +ACI-if a user notices+ACI. Who are the exofs
+AD4 +AD4 users?
+AD4 
+AD4 See my thoughts on this in https://lkml.org/lkml/2018/10/27/27.
+AD4 Particularly the part about the IMO catch 22.
+AD4 
+AD4 Neither you nor I can claim +ACI-there are none.+ACI

That's not completely correct. The standard approach to check whether or not
a driver is still being used is to check its git history. If the number of
contributors is low and it was several years ago that a new feature was added
or a bug has been fixed it is likely that nobody is using that driver anymore.

Bart.